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Fencer Vulns
medium 5.3

CVE-2026-18785 json

o6 open62541 client_types_custom.c UA_Client_getRemoteDataTypes use after free

published 2026-08-04 3 mo ago modified 2026-10-24 16 d ago also EUVD-2026-52792

cvss
5.3
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 5%
public exploits
0
none known

Summary

A vulnerability was determined in o6 open62541 ca356b088ada7dee824d1b4acd07c1ff07ce242b. Impacted is the function UA_Client_getRemoteDataTypes of the file examples/custom_datatype/client_types_custom.c. Executing a manipulation can lead to use after free. It is possible to launch the attack on the local host. The exploit has been publicly disclosed and may be utilized. The project closed the issue report, stating that this is not the official way to report a security vulnerability.

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-18785 updated

open62541: open62541: Use-after-free vulnerability via local manipulation

  • Red Hat All currently supported Red Hat products
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
3 mo ago

Exploit prediction

0.16% chance of exploitation in the next 30 days, higher than 5% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • vuldb.com https://vuldb.com/submit/857052 referenced PoC, tagged "exploit" by a source, unverified
  • github.com https://github.com/open62541/open62541/issues/8131 referenced PoC, tagged "exploit" by a source, unverified
  • github.com https://github.com/gff-cw/information/issues/12 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 4.0 4.8 CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
CNA 3.1 5.3 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:R
CNA 3.0 5.3 CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:R
CNA 2.0 4.3 AV:L/AC:L/Au:S/C:P/I:P/A:P/E:POC/RL:ND/RC:UR
CNA 4.0 1.9 CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CNA 3.1 5.3 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
CNA 2.0 4.3 AV:L/AC:L/Au:S/C:P/I:P/A:P

Affected products

  • o6 open62541

Classification

Weakness
  • CWE-416 Use After Free
  • CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.